Battery cell, battery and electric device

Abstract

The embodiment of the utility model provides a battery monomer, a battery and a power utilization device. The battery cell includes a housing, an electrode assembly, and a detection member. The shell has an accommodating cavity. The electrode assembly is contained in the containing cavity. The detection part comprises a sensor and a connecting piece, the sensor is connected to the shell through the connecting piece, the sensor is used for detecting state information of the single battery and generating a signal, and the connecting piece is used for transmitting the signal. The sensor can detect the state information of the battery monomer in real time, so that the battery monomer is regulated and controlled according to the state information of the battery monomer, the cycle performance of the battery monomer is improved, the safety risk is reduced, and the cycle life of the battery monomer is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and more specifically, to a battery cell, a battery, and an electrical device. Background Art

[0002] Battery monomers are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and electric tools, etc.

[0003] How to improve the safety of battery cells is a research direction in battery technology. Summary of the invention

[0004] The present application provides a battery cell, a battery, and an electrical device, which can improve safety.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, including a housing, an electrode assembly, and a detection component. The housing has a receiving cavity. The electrode assembly is received in the receiving cavity. The detection component includes a sensor and a connector, wherein the sensor is connected to the housing through the connector, and the sensor is used to detect the status information of the battery cell and generate a signal, and the connector is used to transmit the signal.

[0006] The sensor can detect the status information of the battery cell in real time, and then regulate the battery cell according to the status information of the battery cell, improve the cycle performance of the battery cell, reduce safety risks, and extend the cycle life of the battery cell. The connector can simultaneously fix the sensor and transmit the signal, thereby simplifying the structure of the battery cell and reducing the risk of sensor damage.

[0007] In some embodiments, the state information of the battery cell includes at least one of an internal gas pressure of the battery cell, a temperature of the battery cell, an internal gas composition of the battery cell, and a deformation amount of the electrode assembly.

[0008] In some embodiments, the connector includes an optical fiber. Optical fiber sensing technology has high sensitivity, can achieve real-time monitoring, and can promptly alarm when a battery cell has a problem, making it easier to replace the battery cell with a problem, thereby increasing the battery life and saving costs.

[0009] In some embodiments, the sensor includes at least one of a Bragg grating and a Fabry-Perot resonant cavity. By setting the Bragg grating, the changes in temperature and stress inside the battery cell can be conveniently tested. By setting the Fabry-Perot resonant cavity as an air pressure sensor, the air pressure inside the battery cell can be accurately monitored in real time.

[0010] In some embodiments, the housing includes a first wall, the first wall is provided with a first through hole communicating with the accommodation cavity, the sensor is located on a side of the first wall away from the accommodation cavity, and the sensor is configured to detect status information of the battery cell through the first through hole.

[0011] The sensor is arranged outside the first wall, which can facilitate the installation and replacement of the sensor and simplify the assembly process. The sensor can detect the internal state information of the battery cell by opening the first through hole on the first wall.

[0012] In some embodiments, the sensor is opposite to the first through hole in the axial direction of the first through hole. The detection signal emitted by the sensor can enter the accommodation cavity through the first through hole, so that the sensor can detect the internal state information of the battery cell.

[0013] In some embodiments, the sensor is connected to the first wall and covers the first through hole. Connecting the sensor to the first wall can reduce the risk of the sensor shaking when the battery cell vibrates, improve the stability of the sensor, and improve the accuracy of sensor detection. The sensor can cover the first through hole to reduce the risk of electrolyte leakage through the first through hole and improve safety.

[0014] In some embodiments, the detection component further includes a fixing member, and the connecting member is connected to the first wall via the fixing member.

[0015] In some embodiments, the surface of the fixing member facing the first wall abuts against the first wall, and the fixing member is provided with a receiving recess recessed from the surface of the fixing member facing the first wall, and the receiving recess is communicated with the first through hole. The sensor is received in the receiving recess, and the connecting member is connected to the fixing member and passes through the fixing member.

[0016] The fixing piece can protect the sensor from the outside, reduce the risk of the sensor being contaminated or damaged by external impurities, and improve the accuracy of the sensor. The connector passes through the fixing piece to facilitate connection with the device outside the fixing piece.

[0017] In some embodiments, the bottom wall of the accommodating recess is provided with a second through hole, and the connecting member passes through the fixing member via the second through hole. The connecting member entering the accommodating recess via the second through hole can pull up the sensor to connect the sensor to the fixing member, thereby improving the stability of the detection component.

[0018] In some embodiments, the detection component further includes a sealing member, which connects the hole wall of the second through hole and the connecting member and seals the second through hole. The sealing member seals the second through hole to reduce the risk of electrolyte leakage through the second through hole and improve safety. The sealing member can simultaneously serve as a connection between the fixing member and the connecting member and a sealing function, thereby simplifying the structure of the detection component.

[0019] In some embodiments, the sealing member is bonded to the hole wall of the second through hole and the connecting member. The bonding process is easy to implement, and can reduce the risk of damage to the connecting member and improve the accuracy of signal transmission.

[0020] In some embodiments, the fixing member is welded to the first wall. Welding can increase the connection strength of the fixing member and improve the seal, thereby reducing the risk of electrolyte leakage through the gap between the fixing member and the first wall.

[0021] In some embodiments, a positioning recess is provided on a side of the first wall facing away from the accommodating cavity, and the first through hole passes through the bottom wall of the positioning recess. At least a portion of the fixing member is accommodated in the positioning recess.

[0022] The positioning recess can play a positioning role when assembling the fixing member and the first wall, simplifying the assembly process and improving assembly efficiency. The positioning recess can also accommodate at least part of the fixing member to reduce the size of the fixing member protruding from the first wall, reduce the space occupied by the fixing member, and improve the energy density of the battery cell.

[0023] In some embodiments, the fixing member includes a fixing body and a flange surrounding the outside of the fixing body, the fixing body is provided with a receiving recess, at least part of the flange is received in the positioning recess, and the outer peripheral surface of the flange is connected to the side wall of the positioning recess.

[0024] By providing the flange, the distance between the side wall of the positioning recess and the fixed body can be increased, the risk of damaging the fixed body when connecting the flange and the side wall of the positioning recess is reduced, and the sealing is improved.

[0025] In some embodiments, the flange abuts against the bottom wall of the positioning recess to increase the contact area between the first wall and the fixing member and improve the stability of the connection between the first wall and the fixing member.

[0026] In some embodiments, the accommodating recess is stepped and includes a first section and a second section, the second section being located on a side of the first section away from the first through hole. A cross section of the first section perpendicular to the axial direction of the first through hole is smaller than a cross section of the second section perpendicular to the axial direction of the first through hole. The sensor is accommodated in the second section.

[0027] The second section has a larger cross-sectional area to provide sufficient accommodation space for the sensor. The accommodation recess is set to a step shape to reduce the size of the opening of the accommodation recess close to the first through hole, thereby increasing the contact area between the fixed body and the first wall and improving stability.

[0028] In some embodiments, the housing further comprises an electrode terminal disposed on the first wall, the electrode assembly comprises a tab, and the electrode terminal is electrically connected to the tab. In a direction perpendicular to the first wall, an end of the fixing member away from the first wall does not extend beyond the electrode terminal.

[0029] The above technical solution can use the space occupied by the electrode terminal in the direction perpendicular to the first wall to set the fixing member, and the fixing member will not increase the size of the battery cell in the direction perpendicular to the first wall, thereby improving the space utilization and energy density of the battery cell.

[0030] In some embodiments, the battery cell is configured to inject electrolyte through the first through hole. The first through hole is used as the injection hole of the battery cell, and the first through hole is sealed by the detection component, which can reduce the opening of the shell and omit the conventional sealing sheet, thereby simplifying the structure of the battery cell.

[0031] In some embodiments, the housing is provided with a lead-out through hole communicating with the accommodation cavity. The sensor is accommodated in the accommodation cavity, and at least part of the connecting member is accommodated in the lead-out through hole and connected to the housing.

[0032] The sensor is arranged in the accommodating cavity, which can improve the utilization rate of the internal space of the battery cell and improve the accuracy of the sensor in detecting the internal state information of the battery cell. By providing the lead-out through hole, at least part of the connector can be exposed, which facilitates the connector to transmit the signal to the outside of the housing.

[0033] In some embodiments, the detection component further includes a sealing member, which connects the hole wall of the lead-out through hole and the connector and seals the lead-out through hole. The sealing member seals the lead-out through hole to reduce the risk of electrolyte leakage through the lead-out through hole and improve safety. The sealing member can simultaneously perform the function of connecting the hole wall of the lead-out through hole and the connector and the sealing function, thereby simplifying the structure of the detection component.

[0034] In some embodiments, an insulating layer is provided on the surface of the sensor facing the electrode assembly. By providing the insulating layer, the risk of the sensor conducting the positive and negative electrodes when the battery cell vibrates can be reduced, thereby improving safety.

[0035] In some embodiments, the housing includes a first wall, and the sensor is located on a side of the first wall facing the electrode assembly and is spaced apart from the first wall. Spaced apart from the first wall, the sensor can be provided with a movable space, thereby reducing the force at the connection between the sensor and the connector when the battery cell vibrates, reducing the risk of connection failure between the sensor and the connector, and improving the safety of the battery cell.

[0036] In some embodiments, the battery cell is configured to inject electrolyte through the lead-out through hole. The lead-out through hole is used as the injection hole of the battery cell, and the detection component is used to seal the first through hole, which can reduce the opening of the shell and omit the conventional sealing sheet, thereby simplifying the structure of the battery cell.

[0037] In some embodiments, the battery cell further comprises an insulating component disposed on a surface of the first wall facing the electrode assembly. The sensor is located on a side of the insulating component away from the first wall. The insulating component is provided with a first avoidance hole opposite to the lead-out through hole, and the connector extends into the lead-out through hole through the first avoidance hole.

[0038] The insulating component is used to insulate the first wall from the electrode assembly to reduce the risk of the first wall conducting the positive and negative electrodes of the electrode assembly and improve safety. The first avoidance hole is provided to reduce the risk of interference between the insulating component and the connector.

[0039] In some embodiments, the insulating component is spaced apart from the sensor. Space between the sensor and the insulating component can provide a movable space for the sensor, thereby reducing the force on the connection between the sensor and the connector when the battery cell vibrates, reducing the risk of connection failure between the sensor and the connector, and improving the safety of the battery cell.

[0040] In some embodiments, a portion of the connector extends to the outside of the housing through the lead-out hole, so as to facilitate the connection of the connector to a device outside the housing.

[0041] In some embodiments, the housing includes a shell and an end cap, the shell has an opening, and the end cap is used to cover the opening. The end cap is a first wall of the housing. Compared with the shell, the end cap has a greater thickness, and the detection component is arranged on the end cap, so that the detection component can be stably supported and the stability of the detection component is improved.

[0042] In some embodiments, the housing includes an electrode terminal, the electrode assembly includes a tab, and the electrode terminal is electrically connected to the tab. The lead-out through hole is provided on the electrode terminal, and the sensor is provided on a side of the electrode terminal facing the electrode assembly. Providing the lead-out through hole on the electrode terminal can improve the space utilization of the battery cell.

[0043] In some embodiments, the battery cell further includes a transition component for connecting the tab and the electrode terminal. The transition component includes a terminal connection portion that abuts against the surface of the electrode terminal facing the electrode assembly, and the terminal connection portion is provided with a second avoidance hole opposite to the lead-out through hole. The sensor is located on the side of the terminal connection portion away from the electrode terminal, and the connector extends into the lead-out through hole through the second avoidance hole. By providing the second avoidance hole, the risk of the transition component interfering with the connector is reduced, so that the connector can smoothly extend into the lead-out through hole.

[0044] In some embodiments, the terminal connection part is spaced apart from the sensor. Spaced apart from the terminal connection part, the sensor can be provided with a movable space, thereby reducing the force on the connection between the sensor and the connector when the battery cell vibrates, reducing the risk of connection failure between the sensor and the connector, and improving the safety of the battery cell.

[0045] In some embodiments, the connector does not protrude from the surface of the electrode terminal away from the electrode assembly. The surface of the electrode terminal away from the electrode assembly usually needs to be connected to the busbar component, and the above technical solution can reduce the risk of interference between the connector and the busbar component.

[0046] In some embodiments, the adapter component includes an adapter body and an adapter protrusion, the adapter body is connected to the pole ear, and the adapter protrusion protrudes from the surface of the adapter body facing the electrode terminal. The adapter component forms an adapter recess at a position corresponding to the adapter protrusion, and the bottom wall of the adapter recess forms a terminal connection portion. The sensor is accommodated in the adapter recess. The sensor is arranged in the adapter recess to improve space utilization. The side wall of the adapter recess can limit the sensor to reduce the amplitude of the sensor shaking when the battery cell vibrates.

[0047] In some embodiments, the battery cells are cylindrical battery cells or prismatic battery cells.

[0048] In a second aspect, an embodiment of the present application provides a battery, comprising a plurality of battery cells provided by any embodiment of the first aspect.

[0049] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery cell provided by any embodiment of the first aspect, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without paying creative work.

[0051] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0052] Figure 2 Schematic diagram of an explosion of a battery provided in some embodiments of the present application

[0053] Figure 3 A schematic diagram of a three-dimensional structure of a battery cell provided in some embodiments of the present application;

[0054] Figure 4 for Figure 3 A schematic cross-sectional view of a battery cell is shown;

[0055] Figure 5 for Figure 4 An enlarged schematic diagram at the circle A;

[0056] Figure 6A partial cross-sectional schematic diagram of a battery cell provided in some other embodiments of the present application;

[0057] Figure 7 A partial cross-sectional schematic diagram of a battery cell provided in some other embodiments of the present application;

[0058] Figure 8 A schematic cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0059] Fig. 9 A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application;

[0060] Fig.10 for Fig. 9 A schematic cross-sectional view of a battery cell is shown;

[0061] Fig.11 A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application;

[0062] Fig.12 for Fig.11 A schematic cross-sectional view of a battery cell is shown;

[0063] Fig.13 for Fig.12 An enlarged schematic diagram at the circle B;

[0064] Fig.14 A schematic cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0065] Fig.15 A schematic cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0066] Fig.16 for Fig.15 An enlarged schematic diagram at circle C.

[0067] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION

[0068] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0069] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0070] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0071] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0072] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0073] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0074] The term "plurality" used in the present application refers to two or more (including two).

[0075] In the present application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell or a magnesium-ion battery cell, etc., and the embodiments of the present application do not limit this. The battery cell may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this.

[0076] In the present application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell or a magnesium-ion battery cell, etc., and the embodiments of the present application do not limit this. The battery cell may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this.

[0077] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0078] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. A battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector includes a positive coating area and a positive electrode ear connected to the positive coating area. The positive coating area is coated with a positive active material layer, and the positive electrode ear is not coated with a positive active material layer. Taking a lithium-ion battery cell as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material. The positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector; the negative electrode current collector includes a negative electrode coating area and a negative electrode tab connected to the negative electrode coating area, and the negative electrode coating area is coated with a negative electrode active material layer, and the negative electrode tab is not coated with a negative electrode active material layer. The material of the negative electrode current collector can be copper, and the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material can be carbon or silicon, etc. The material of the separator can be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene), etc.

[0079] The battery cell further includes a housing, and a housing is formed inside the housing to accommodate the electrode assembly. The housing can protect the electrode assembly from the outside to prevent external foreign matter from affecting the charging or discharging of the electrode assembly.

[0080] During the cycle of battery cells, abnormal conditions may occur. For example, after multiple charge and discharge cycles, side reactions may occur inside the battery cells and gas may continue to be generated. The gas will increase the air pressure inside the battery cells, thereby causing the risk of shell deformation and rupture. For another example, when a short circuit occurs inside the battery cells, the battery cells generate heat and the temperature rises, thereby causing the risk of thermal runaway of the battery cells.

[0081] During the use of the battery, if the abnormal conditions of the battery cells cannot be detected and handled in a timely manner, the battery cells will deteriorate and cause safety accidents.

[0082] The inventor tried to set up a detection component on the battery circuit board to detect the working status of the battery cell in real time, so as to determine whether the battery cell is abnormal. However, the inventor found that the space on the circuit board is limited, and it is difficult to test each battery cell individually, resulting in deviations in the test results.

[0083] In view of this, an embodiment of the present application provides a technical solution, which integrates a detection component into a battery cell to detect the status information of each battery cell in real time, thereby regulating the battery cell according to the status information of the battery cell, improving the cycle performance of the battery cell, reducing safety risks, and extending the cycle life of the battery cell.

[0084] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0085] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like; the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like; the electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0086] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0087] Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application.

[0088] like Figure 1As shown, a battery 2 is disposed inside the vehicle 1, and the battery 2 may be disposed at the bottom, head, or tail of the vehicle 1. The battery 2 may be used to power the vehicle 1, for example, the battery 2 may be used as an operating power source for the vehicle 1.

[0089] The vehicle 1 may further include a controller 3 and a motor 4 , wherein the controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements of starting, navigating, and driving the vehicle 1 .

[0090] In some embodiments of the present application, the battery 2 can not only serve as an operating power source for the vehicle 1, but also serve as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0091] Figure 2 An exploded schematic diagram of a battery provided for some embodiments of the present application.

[0092] like Figure 2 As shown, the battery 2 includes a case 5 and a battery cell 6 (not shown), and the battery cell 6 is accommodated in the case 5 .

[0093] The box 5 is used to accommodate the battery cell 6, and the box 5 can be of various structures. In some embodiments, the box 5 can include a first box portion 5a and a second box portion 5b, the first box portion 5a and the second box portion 5b cover each other, and the first box portion 5a and the second box portion 5b jointly define a storage space 5c for accommodating the battery cell 6. The second box portion 5b can be a hollow structure with one end open, the first box portion 5a is a plate-like structure, and the first box portion 5a covers the open side of the second box portion 5b to form a box 5 with a storage space 5c; the first box portion 5a and the second box portion 5b can also be hollow structures with one side open, and the open side of the first box portion 5a covers the open side of the second box portion 5b to form a box 5 with a storage space 5c. Of course, the first box portion 5a and the second box portion 5b can be of various shapes, such as a cylinder, a cuboid, etc.

[0094] In order to improve the sealing performance after the first box body part 5a and the second box body part 5b are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body part 5a and the second box body part 5b.

[0095] Assuming that the first box body portion 5a covers the top of the second box body portion 5b, the first box body portion 5a can also be called an upper box cover, and the second box body portion 5b can also be called a lower box.

[0096] In the battery 2, there can be one or more battery cells 6. If there are more than one battery cell 6, the battery cells 6 can be connected in series, in parallel or in mixed connection. Mixed connection means that the battery cells 6 are both connected in series and in parallel. The battery cells 6 can be directly connected in series, in parallel or in mixed connection, and then the whole formed by the battery cells 6 can be accommodated in the box 5; of course, the battery cells 6 can also be connected in series, in parallel or in mixed connection to form a battery module, and then the battery modules can be connected in series, in parallel or in mixed connection to form a whole, and then accommodated in the box 5.

[0097] Figure 3 A schematic diagram of a three-dimensional structure of a battery cell provided in some embodiments of the present application; Figure 4 for Figure 3 A schematic cross-sectional view of a battery cell is shown; Figure 5 for Figure 4 Enlarged schematic diagram at circle A.

[0098] Reference Figures 3 to 5 The embodiment of the present application provides a battery cell 6, which includes a housing 20, an electrode assembly 10 and a detection component 30. The housing 20 has a receiving cavity 20a. The electrode assembly 10 is received in the receiving cavity 20a. The detection component 30 is connected to the housing 20 and is used to detect the status information of the battery cell 6.

[0099] The housing 20 is a hollow structure, and a receiving cavity 20a is formed inside the housing 20 for receiving the electrode assembly 10 and the electrolyte. The shape of the housing 20 can be determined according to the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 is a rectangular parallelepiped structure, a rectangular housing can be selected; if the electrode assembly 10 is a cylindrical structure, a cylindrical housing can be selected.

[0100] The material of the housing 20 can be various, for example, the material of the housing 20 can be metal or plastic. Optionally, the material of the housing 20 can be copper, iron, aluminum, steel, aluminum

[0101] The electrode assembly 10 includes a positive electrode sheet and a negative electrode sheet. Exemplarily, the electrode assembly 10 generates electrical energy through oxidation and reduction reactions when ions are embedded / extracted from the positive electrode sheet and the negative electrode sheet. Optionally, the electrode assembly 10 also includes a separator, which is used to insulate and isolate the positive electrode sheet and the negative electrode sheet.

[0102] The electrode assembly 10 may be a wound electrode assembly, a laminated electrode assembly, or other types of electrode assemblies.

[0103] There may be one or more electrode assemblies 10. When there are more than one electrode assemblies 10, the plurality of electrode assemblies 10 may be stacked.

[0104] The status information of the battery cell 6 is information characterizing the working status of the battery cell 6. Exemplarily, the status information of the battery cell 6 may include at least one of the status information such as the internal air pressure of the battery cell, the temperature of the battery cell, the internal gas composition of the battery cell, the deformation of the electrode assembly, the deformation of the outer shell, the dendrite growth condition inside the electrode assembly, and the charge inside the battery cell.

[0105] The detection component 30 may be disposed entirely inside the housing 20 or outside the housing 20. Alternatively, a portion of the detection component 30 may be disposed inside the housing 20 and a portion may be disposed outside the housing 20.

[0106] The detection component 30 may be directly connected to the housing 20 , or may be indirectly connected to the housing 20 via other components.

[0107] In the application embodiment, the detection component 30 is integrated into the battery cell 6 to detect the status information of the battery cell 6 in real time, so that the battery cell 6 is regulated according to the status information of the battery cell 6, thereby improving the cycle performance of the battery cell 6, reducing safety risks, and extending the cycle life of the battery cell 6.

[0108] In some embodiments, the detection component 30 includes a sensor 31 and a connector 32 . The sensor 31 is connected to the housing 20 via the connector 32 . The sensor 31 is used to detect status information of the battery cell 6 and generate a signal. The connector 32 is used to transmit the signal.

[0109] The sensor 31 may be a resistive sensor, an inductive sensor, a capacitive sensor, a piezoelectric sensor, a magnetoelectric sensor, a thermoelectric sensor, a photoelectric sensor, a digital sensor, a fiber optic sensor, an ultrasonic sensor, a thermal sensor, or other types of sensors.

[0110] The number of the sensor 31 of the detection component 30 may be one or more.

[0111] The sensor 31 may be disposed in the accommodating cavity 20 a of the housing 20 , or may be disposed outside the housing 20 .

[0112] The connecting member 32 may be directly connected to the housing 20 or indirectly connected to the housing 20 via other components. The sensor 31 is fixed to the housing 20 via the connecting member 32 .

[0113] The connector 32 can be used to transmit signals. For example, the connector 32 can be used to transmit the signal generated by the sensor 31 to the data processing unit of the battery, and can also transmit the signal sent by the data processing unit to the sensor 31. For example, the signal transmission between the connector 32 and the data processing unit can be achieved through a cable, or through wireless transmission technology.

[0114] In the embodiment of the present application, the sensor 31 can detect the status information of the battery cell 6 in real time, thereby regulating the battery cell 6 according to the status information of the battery cell 6, improving the cycle performance of the battery cell 6, reducing safety risks, and extending the cycle life of the battery cell 6. The connector 32 can simultaneously play the function of fixing the sensor 31 and the function of transmitting signals, thereby simplifying the structure of the battery cell 6 and reducing the risk of damage to the sensor 31.

[0115] In some embodiments, the status information of the battery cell 6 includes at least one of the internal gas pressure of the battery cell, the temperature of the battery cell, the internal gas composition of the battery cell, and the deformation amount of the electrode assembly.

[0116] For example, the sensor 31 may include a temperature sensor, which may be disposed outside the housing 20 and in contact with the housing 20 to detect the temperature of the housing 20. Alternatively, the temperature sensor may be disposed in the receiving cavity 20a of the housing 20 and detect the temperature inside the battery cell 6.

[0117] For example, the sensor 31 may include a hydrogen sensor. The hydrogen sensor 31 may be disposed in the accommodating cavity 20a of the housing 20 to detect the hydrogen component inside the battery cell 6. Alternatively, the hydrogen sensor may also be disposed outside the housing 20, and a channel may be provided on the housing 20, and the gas inside the battery cell 6 may act on the hydrogen sensor through the channel.

[0118] Of course, the sensor 31 may also include sensors for detecting other components.

[0119] Exemplarily, the sensor 31 may include an air pressure sensor. The air pressure sensor may be disposed in the accommodating cavity 20a of the housing 20 to detect the air pressure inside the battery cell 6. Alternatively, the air pressure sensor may also be disposed outside the housing 20, and a channel may be provided on the housing 20, and the gas inside the battery cell 6 may act on the air pressure sensor through the channel.

[0120] For example, the sensor 31 may include a displacement sensor. The displacement sensor may be disposed in the accommodation cavity 20a of the housing 20 and abut against the electrode assembly 10. The displacement sensor may measure the expansion and deformation amount of the electrode assembly 10 during the charge and discharge process.

[0121] For example, the sensor 31 may include a stress sensor. The stress sensor may be inserted between the positive and negative electrode sheets of the electrode assembly 10 to measure stress changes between the positive and negative electrode sheets.

[0122] In some embodiments, the connector 32 comprises an optical fiber. Exemplarily, the optical fiber and the sensor 31 constitute an optical fiber sensor.

[0123] At the heart of fiber optic sensing technology is the optical fiber - a thin glass strand through which light waves can propagate. Optical fiber consists of three main parts: the core, the cladding, and the protective layer. The cladding reflects stray light waves from the core back into the core to ensure that the light waves have the lowest transmission loss in the core. This works because the refractive index of the core is higher than that of the cladding, so that total internal reflection occurs when the light waves propagate from the core to the cladding. The outermost protective layer provides protection from damage to the fiber caused by the external environment or external forces.

[0124] The diameter of the optical fiber is between 10μm and 10mm, and the material is high-purity quartz glass or all-plastic optical fiber. The length can be customized as needed. The protective layer outside the optical fiber is made of acrylic, silicone rubber, nylon, polyimide and other materials.

[0125] The optical fiber sensing technology has high sensitivity and can realize real-time monitoring. It can promptly alarm when a problem occurs in the battery cell 6, making it easy to replace the problematic battery cell 6, thereby increasing the battery life and saving costs.

[0126] In some embodiments, the sensor 31 includes at least one of a Bragg grating and a Fabry-Perot cavity.

[0127] FBG refers to fiber Bragg grating, which is a spatial phase periodic grating formed in the core of the optical fiber. Its essence is to form a narrow-band filter and reflector in the core of the optical fiber.

[0128] Fiber Bragg Grating (FBG) sensor is the most frequently used and widely used fiber optic sensor. This sensor can change the wavelength of the reflected light wave according to the change of ambient temperature and / or strain. Fiber Bragg Grating is to expose a short section of light-sensitive optical fiber to a light wave with a periodic distribution of light intensity through holographic interferometry or phase mask method. In this way, the refractive index of the optical fiber will change permanently according to the intensity of the light wave it is exposed to. The periodic change of the refractive index of light caused by this method is called fiber Bragg grating.

[0129] When a broad-spectrum light beam is transmitted to a fiber Bragg grating, each small section of the optical fiber after the light refractive index is changed will only reflect a specific wavelength of light, which is called the Bragg wavelength. This characteristic makes the fiber Bragg grating reflect only a specific wavelength of light, while other wavelengths of light will be transmitted.

[0130] Tilted Fiber Bragg Grating has been a research hotspot for fiber optic sensors in recent years. Using optical methods to write tilted Fiber Bragg Grating on the fiber core can break the cylindrical symmetry of the mode coupling process, and promote the coupling of light from the core to different cladding modes. The spectrum of this fiber grating sensor is an excellent narrow-band resonance peak comb spectrum, which provides a high-precision measurement tool for monitoring various small modulation changes. The cutoff mode in the cladding mode of the tilted Fiber Bragg Grating has a deep evanescent wave light field intensity and penetration depth, and has a very high sensitivity to changes in the ambient refractive index. Therefore, the cutoff mode can be used to measure the external environmental refractive index and dendrite growth, etc., providing a high-precision measurement method for the growth of dendrites on the surface of the internal electrode of the battery.

[0131] By providing the Bragg grating, changes in the temperature and stress inside the battery cell 6 can be conveniently tested.

[0132] FP cavity, also known as Fabry-Pérot cavity, is a type of optical cavity consisting of two parallel plane mirrors and is commonly used in semiconductor lasers.

[0133] From the basic principle, the fiber optic sensor will change one or several properties of the propagating light waves, such as intensity, phase, polarization state, and frequency, according to the changes in the external environmental parameters being tested. Non-intrinsic (hybrid) fiber optic sensors only use the optical fiber as the transmission medium between the device and the sensor element, while intrinsic fiber optic sensors use the optical fiber itself as the sensor element.

[0134] In optics, a Fabry-Perot cavity interferometer is a multi-beam interferometer consisting of two parallel glass plates, where the opposing inner surfaces of the two glass plates have high reflectivity. The Fabry-Perot interferometer is also often called a Fabry-Perot cavity, FP cavity, or Fabry-Perot cavity, and when the two glass plates are fixed with a hollow spacer of fixed length, it is also called a Fabry-Perot etalon or simply an etalon, but these terms are not strictly distinguished when used. The characteristic of this interferometer is that when the frequency of the incident light meets its resonance condition, its transmission spectrum will have a very high peak, corresponding to a very high transmittance. The resonance characteristics of the Fabry-Perot interferometer are the same as the resonance characteristics used by dichroic filters.

[0135] By providing a Fabry-Perot resonant cavity as an air pressure sensor, the air pressure inside the battery cell 6 can be accurately monitored in real time.

[0136] In some embodiments, the housing 20 includes a shell 21 and an end cover 22 , the shell 21 has an opening, and the end cover 22 is used to cover the opening.

[0137] The housing 21 and the end cover 22 enclose a receiving chamber 20a.

[0138] The shell 21 can be in various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, etc. Specifically, the shape of the shell 21 can be determined according to the specific shape and size of the electrode assembly 10. The shell 21 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0139] The shape of the end cap 22 can be adapted to the shape of the housing 21 to match the housing 21. Optionally, the end cap 22 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 22 is not easily deformed when squeezed and collided, so that the battery cell 6 can have a higher structural strength and the safety performance can also be improved. The end cap 22 is connected to the housing 21 by welding, bonding, clamping or other methods.

[0140] The housing 21 may be a structure with one side open, and one end cap 22 is provided to cover the opening of the housing 21. Alternatively, the housing 21 may be a structure with two sides open, and two end caps 22 are provided, and the two end caps 22 cover the two openings of the housing 21 respectively.

[0141] In some embodiments, the battery cell 6 is a cylindrical battery cell. Exemplarily, the housing 20 of the battery cell 6 is cylindrical.

[0142] In some embodiments, the battery cell 6 is a square battery cell. Exemplarily, the housing 20 of the battery cell 6 is a rectangular parallelepiped.

[0143] In some embodiments, the housing 20 includes a first wall 20b having a first through hole 221 communicating with the accommodating cavity 20a. The sensor 31 is located on a side of the first wall 20b away from the accommodating cavity 20a and is configured to detect status information of the battery cell 6 through the first through hole 221.

[0144] The first wall 20 b may be an end cover 22 or a part of the housing 21 .

[0145] There may be one or more first through holes 221 .

[0146] The sensor 31 is arranged outside the first wall 20b, which can facilitate the installation and replacement of the sensor 31 and simplify the assembly process. By opening the first through hole 221 on the first wall 20b, the sensor 31 can detect the internal state information of the battery cell 6.

[0147] For example, the sensor 31 may detect the gas pressure, temperature, gas composition or other status information inside the battery cell 6 .

[0148] In some embodiments, in the axial direction X of the first through hole 221 , the sensor 31 is opposite to the first through hole 221 .

[0149] In the axial direction X of the first through hole 221 , the projection of the sensor 31 at least partially overlaps with the projection of the first through hole 221 .

[0150] The sensor 31 may close the first through hole 221 ; alternatively, in the axial direction X of the first through hole 221 , the sensor 31 may also be spaced apart from the first through hole 221 .

[0151] The detection signal (eg, light) emitted by the sensor 31 can enter the accommodation cavity 20 a through the first through hole 221 , so that the sensor 31 can detect the internal state information of the battery cell 6 .

[0152] In some embodiments, the detection component 30 further includes a fixing member 33 , and the connecting member 32 is connected to the first wall 20 b via the fixing member 33 .

[0153] The fixing member 33 can be fixed to the first wall 20 b by welding, bonding, clamping or other methods.

[0154] The connecting member 32 may be directly connected to the fixing member 33, or indirectly connected to the fixing member 33 through other components. For example, the connecting member 32 may be bonded by colloid, or may be integrally formed with the fixing member 33 by hot melting.

[0155] For example, the fixing member 33 , the sensor 31 and the connecting member 32 of the detection component 30 may be pre-assembled together. When the detection component 30 and the housing 20 are assembled, the fixing member 33 may be fixed to the first wall 20 b of the housing 20 .

[0156] In some embodiments, the surface of the fixing member 33 facing the first wall 20b abuts against the first wall 20b, and the fixing member 33 is provided with a receiving recess 331 recessed from the surface of the fixing member 33 facing the first wall 20b, and the receiving recess 331 is communicated with the first through hole 221. The sensor 31 is received in the receiving recess 331, and the connecting member 32 is connected to the fixing member 33 and passes through the fixing member 33.

[0157] The connecting member 32 may pass through the bottom wall of the accommodating recess 331 , or may pass through the side wall of the accommodating recess 331 .

[0158] The fixing member 33 can protect the sensor 31 from the outside, reduce the risk of the sensor 31 being contaminated or damaged by external impurities, and improve the accuracy of the sensor 31. The connecting member 32 passes through the fixing member 33 to facilitate connection with a device outside the fixing member 33.

[0159] In some embodiments, a second through hole 332 is defined on the bottom wall of the accommodating recess 331 , and the connecting member 32 passes through the fixing member 33 via the second through hole 332 .

[0160] The connecting member 32 entering the accommodating recess 331 via the second through hole 332 can pull up the sensor 31 to connect the sensor 31 to the fixing member 33 , thereby improving the stability of the detecting component 30 .

[0161] Exemplarily, the connecting member 32 may be connected to a side of the sensor 31 facing away from the first through hole 221 .

[0162] For example, the connecting member 32 may be a flexible structure. The connecting member 32 can pull up the sensor 31, so the flexible connecting member 32 can also fix the sensor 31. The flexible connecting member 32 is deformable, which is convenient for connection with other components.

[0163] In some embodiments, the detection component 30 further includes a sealing member 34 , which connects a hole wall of the second through hole 332 and the connecting member 32 , and seals the second through hole 332 .

[0164] The sealing member 34 may be connected to the hole wall of the second through hole 332 and the connecting member 32 by bonding, interference fit, welding or other methods.

[0165] The seal 34 seals the second through hole 332 to reduce the risk of electrolyte leakage through the second through hole 332 and improve safety. The seal 34 can simultaneously connect the fixing member 33 and the connecting member 32 and seal, thereby simplifying the structure of the detection component 30.

[0166] In some embodiments, the sealing member 34 is bonded to the hole wall of the second through hole 332 and the connecting member 32 .

[0167] For example, a colloid may be filled between the hole wall of the second through hole 332 and the connecting member 32 , and the sealing member 34 is formed after the colloid is cured.

[0168] The bonding process is easy to implement, and can reduce the risk of damage to the connector 32 and improve the accuracy of signal transmission.

[0169] In some embodiments, the fixing member 33 is welded to the first wall 20b. Welding can increase the connection strength of the fixing member 33 and improve the sealing, thereby reducing the risk of electrolyte leakage through the gap between the fixing member 33 and the first wall 20b.

[0170] In some embodiments, the fixing member 33 may be a metal member or a plastic member. Optionally, the fixing member 33 is a metal member, which has high strength to stably support the connecting member 32 and the sensor 31 .

[0171] In some embodiments, a positioning recess 222 is provided on one side of the first wall 20b away from the accommodating cavity 20a, and the first through hole 221 passes through the bottom wall of the positioning recess 222. At least a portion of the fixing member 33 is accommodated in the positioning recess 222.

[0172] The positioning recess 222 can play a positioning role when assembling the fixing member 33 and the first wall 20b, simplifying the assembly process and improving the assembly efficiency. The positioning recess 222 can also accommodate at least part of the fixing member 33 to reduce the size of the fixing member 33 protruding from the first wall 20b, reduce the space occupied by the fixing member 33, and improve the energy density of the battery cell 6.

[0173] In some embodiments, the fixing member 33 includes a fixing body 333 and a flange 334 surrounding the outer side of the fixing body 333. The fixing body 333 is provided with a receiving recess 331, at least part of the flange 334 is received in the positioning recess 222, and the outer peripheral surface of the flange 334 is connected to the side wall of the positioning recess 222.

[0174] By providing the flange 334 , the distance between the side wall of the positioning recess 222 and the fixing body 333 can be increased, thereby reducing the risk of damaging the fixing body 333 when connecting the flange 334 and the side wall of the positioning recess 222 , and improving the sealing performance.

[0175] For example, the laser can act on the junction of the flange 334 and the side wall of the positioning recess 222 to weld the flange 334 and the side wall of the positioning recess 222. By providing the flange 334, the distance between the side wall of the positioning recess 222 and the fixed body 333 can be increased, reducing the risk of interference between the fixed body 333 and the welding equipment.

[0176] In some embodiments, the flange 334 abuts against the bottom wall of the positioning recess 222 to increase the contact area between the first wall 20 b and the fixing member 33 and improve the stability of the connection between the first wall 20 b and the fixing member 33 .

[0177] In some embodiments, the flange 334 and the fixing body 333 are bonded to the bottom wall of the positioning recess 222 .

[0178] In some embodiments, a surface of the flange 334 facing the bottom wall of the positioning recess 222 is flush with a surface of the fixing body 333 facing the bottom wall of the positioning recess 222 .

[0179] In some embodiments, the end cap 22 is the first wall 20b of the housing 20. Compared with the housing 21, the end cap 22 has a greater thickness, and the detection component 30 is arranged on the end cap 22, so that the detection component 30 can be stably supported and the stability of the detection component 30 can be improved.

[0180] In some embodiments, the battery cell 6 is configured to be injected with electrolyte through the first through hole 221 .

[0181] During the production of battery cells, electrolyte needs to be injected into the interior of the shell. In order to achieve the injection of electrolyte, it is usually necessary to open an injection hole on the battery cell. After the process related to the injection hole is completed, a sealing sheet needs to be provided on the shell to seal the injection hole.

[0182] In the embodiment of the present application, the first through hole 221 is used as the injection hole of the battery cell 6, and the detection component 30 is used to seal the first through hole 221, which can reduce the opening of the shell 20 and eliminate the conventional sealing sheet, thereby simplifying the structure of the battery cell 6.

[0183] Figure 6 A partial cross-sectional schematic diagram of a battery cell provided in some other embodiments of the present application.

[0184] like Figure 6 As shown, in some embodiments, the accommodating recess 331 is stepped and includes a first section 331a and a second section 331b, wherein the second section 331b is located on a side of the first section 331a away from the first through hole 221. The cross section of the first section 331a perpendicular to the axial direction X of the first through hole 221 is smaller than the cross section of the second section 331b perpendicular to the axial direction X of the first through hole 221. The sensor 31 is accommodated in the second section 331b.

[0185] The second section 331b has a larger cross-sectional area to provide sufficient accommodation space for the sensor 31. The accommodation recess 331 is set to be stepped to reduce the size of the opening of the accommodation recess 331 close to the first through hole 221, thereby increasing the contact area between the fixed body 333 and the first wall 20b and improving stability.

[0186] In some embodiments, the fixing body 333 may be bonded to the first wall 20b. By providing the receiving recess 331 in a stepped shape, the bonding area between the fixing body 333 and the first wall 20b may be increased.

[0187] Figure 7 A partial cross-sectional schematic diagram of a battery cell provided in some other embodiments of the present application.

[0188] like Figure 7 As shown, in some embodiments, the sensor 31 is connected to the first wall 20 b and covers the first through hole 221 .

[0189] Connecting the sensor 31 to the first wall 20b can reduce the risk of the sensor 31 shaking when the battery cell 6 vibrates, improve the stability of the sensor 31, and improve the detection accuracy of the sensor 31. The sensor 31 can cover the first through hole 221 to reduce the risk of electrolyte leakage through the first through hole 221 and improve safety.

[0190] In some embodiments, the sensor 31 is bonded to the first wall 20b.

[0191] Figure 8 Schematic cross-sectional views of battery cells provided in some other embodiments of the present application.

[0192] like Figure 8 As shown, in some embodiments, the housing 20 further includes an electrode terminal 23 disposed on the first wall 20b, the electrode assembly 10 includes a tab 11, and the electrode terminal 23 is electrically connected to the tab 11. In a direction perpendicular to the first wall 20b, an end of the fixing member 33 away from the first wall 20b does not extend beyond the electrode terminal 23.

[0193] The electrode terminal 23 is used to electrically connect the electrode assembly 10 to the circuit outside the battery cell 6 to realize the charge and discharge of the electrode assembly 10. Optionally, the electrode terminal 23 is used to connect to the busbar component to realize the electrical connection between the battery cells 6.

[0194] For example, the electrode terminal 23 may protrude from the outer surface of the first wall 20 b away from the accommodating cavity 20 a , so as to facilitate the connection between the electrode terminal 23 and the busbar component and reduce the risk of the first wall 20 b interfering with the busbar component.

[0195] The embodiment of the present application can utilize the space occupied by the electrode terminal 23 in the direction perpendicular to the first wall 20b to set the fixing member 33, that is, the fixing member 33 will not additionally increase the size of the battery cell 6 in the direction perpendicular to the first wall 20b, thereby improving the space utilization and energy density of the battery cell 6.

[0196] In some embodiments, the battery cell 6 is a prismatic battery cell.

[0197] Fig. 9 A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application; Fig.10 for Fig. 9 A schematic cross-sectional view of a battery cell is shown.

[0198] like Fig. 9 and Fig.10 As shown, in some embodiments, the battery cell 6 is a cylindrical battery cell.

[0199] In some embodiments, cylindrical battery cells and square battery cells may use the same detection components.

[0200] In some embodiments, the housing 20 of the battery cell 6 includes a top wall, a side wall and a bottom wall. The side wall may be cylindrical, and the top wall and the bottom wall are both disc-shaped and are respectively connected to the two ends of the side wall. Optionally, the first wall 20b may be the top wall or the bottom wall.

[0201] Fig.11A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application; Fig.12 for Fig.11 A schematic cross-sectional view of a battery cell is shown; Fig.13 for Fig.12 An enlarged schematic diagram at circle B.

[0202] like Figures 11 to 13 As shown, in some embodiments, the housing 20 is provided with an outlet hole 40 communicating with the accommodation cavity 20 a. The sensor 31 is accommodated in the accommodation cavity 20 a, and at least part of the connector 32 is accommodated in the outlet hole 40 and connected to the housing 20 .

[0203] The connecting member 32 may extend to the outside of the housing 20 through the lead-out through hole 40 , or may not extend to the outside of the housing 20 .

[0204] The sensor 31 is arranged in the accommodating cavity 20a, so as to improve the utilization rate of the internal space of the battery cell 6 and improve the accuracy of the sensor 31 in detecting the internal state information of the battery cell 6. By providing the lead-out through hole 40, at least part of the connector 32 can be exposed, so that the connector 32 can transmit the signal to the outside of the housing 20.

[0205] In some embodiments, the connecting member 32 is located on a side of the sensor 31 facing the lead-out through hole 40 .

[0206] In some embodiments, the detection component 30 further includes a sealing member 34 , which connects the hole wall of the lead-out through hole 40 and the connecting member 32 , and seals the lead-out through hole 40 .

[0207] The sealing member 34 may be connected to the hole wall of the lead-out through hole 40 and the connecting member 32 by bonding, interference fit, welding or other methods.

[0208] The seal 34 seals the lead-out hole 40 to reduce the risk of electrolyte leakage through the lead-out hole 40 and improve safety. The seal 34 can simultaneously connect the hole wall of the lead-out hole 40 and the connector 32 and seal, thereby simplifying the structure of the detection component 30.

[0209] In some embodiments, the sealing member 34 is bonded to the hole wall of the lead-out through hole 40 and the connecting member 32. For example, a colloid may be filled between the hole wall of the lead-out through hole 40 and the connecting member 32, and the sealing member 34 is formed after the colloid is cured.

[0210] In some embodiments, an insulating layer 35 is provided on the surface of the sensor 31 facing the electrode assembly 10 .

[0211] By providing the insulating layer 35 , the risk of the sensor 31 conducting the positive and negative electrodes when the battery cell 6 vibrates can be reduced, thereby improving safety.

[0212] In some embodiments, other surfaces of the sensor 31 may be provided with an insulating layer 35. For example, the surface of the sensor 31 facing away from the electrode assembly 10 may also be provided with an insulating layer 35. Exemplarily, the insulating layer 35 may be formed by spraying an insulating material on the surface of the sensor 31.

[0213] In some embodiments, the housing 20 includes a first wall 20 b , and the sensor 31 is located on a side of the first wall 20 b facing the electrode assembly 10 and is spaced apart from the first wall 20 b .

[0214] The first wall 20b may be an end cover 22, or may be a part of the housing 21. Exemplarily, the first wall 20b is the end cover 22.

[0215] If the sensor 31 contacts the first wall 20b, when the battery cell 6 vibrates, stress concentration may occur at the connection between the sensor 31 and the connector 32, causing the risk of failure of the connection between the sensor 31 and the connector 32. In the embodiment of the present application, the sensor 31 is spaced apart from the first wall 20b, which can provide a movable space for the sensor 31, thereby reducing the force at the connection between the sensor 31 and the connector 32 when the battery cell 6 vibrates, reducing the risk of failure of the connection between the sensor 31 and the connector 32, and improving the safety of the battery cell 6.

[0216] In some embodiments, the connector 32 may be bonded to the first wall 20 b or may be integrally formed with the first wall 20 b by hot melt.

[0217] In some embodiments, the battery cell 6 is configured to be injected with electrolyte via the lead-out through-hole 40 .

[0218] The lead-out through hole 40 is used as the liquid injection hole of the battery cell 6 , and the detection component 30 is used to seal the first through hole 221 , which can reduce the openings of the housing 20 and omit the conventional sealing sheet, thereby simplifying the structure of the battery cell 6 .

[0219] In some embodiments, the battery cell 6 further includes an insulating component 50, which is disposed on the surface of the first wall 20b facing the electrode assembly 10. The sensor 31 is located on the side of the insulating component 50 away from the first wall 20b. The insulating component 50 is provided with a first avoidance hole 51 opposite to the lead-out through hole 40, and the connector 32 extends into the lead-out through hole 40 via the first avoidance hole 51.

[0220] In the axial direction Y of the outlet through hole 40 , the first avoidance hole 51 and the outlet through hole 40 at least partially overlap.

[0221] The insulating component 50 is used to insulate the first wall 20b from the electrode assembly 10 to reduce the risk of the first wall 20b conducting the positive and negative electrodes of the electrode assembly 10 and improve safety. The first avoidance hole 51 is provided to reduce the risk of interference between the insulating component 50 and the connector 32.

[0222] In some embodiments, the insulating component 50 is spaced apart from the sensor 31 .

[0223] Setting the sensor 31 apart from the insulating component 50 can provide space for the sensor 31 to move, thereby reducing the force at the connection between the sensor 31 and the connector 32 when the battery cell 6 vibrates, reducing the risk of connection failure between the sensor 31 and the connector 32, and improving the safety of the battery cell 6.

[0224] In some embodiments, a portion of the connector 32 extends to the outside of the housing 20 through the lead-out hole 40 .

[0225] Exemplarily, the connection member 32 protrudes from the outer surface of the housing 20. Optionally, the connection member 32 protrudes from the outer surface of the first wall 20b.

[0226] The connector 32 extends to the outside of the housing 20 so as to be connected to a device outside the housing 20 .

[0227] Fig.14 Schematic cross-sectional views of battery cells provided in some other embodiments of the present application.

[0228] like Fig.14 As shown, in some embodiments, the battery cell 6 is a cylindrical battery cell.

[0229] In some embodiments, the housing 20 is provided with an outlet hole 40 communicating with the accommodation cavity 20 a. The sensor 31 is accommodated in the accommodation cavity 20 a, and at least a portion of the connector 32 is accommodated in the outlet hole 40 and connected to the housing 20 .

[0230] Fig.15 A schematic cross-sectional view of a battery cell provided in some other embodiments of the present application; Fig.16 for Fig.15 An enlarged schematic diagram at circle C.

[0231] like Fig.15 and Fig.16 As shown, in some embodiments, the housing 20 includes an electrode terminal 23, the electrode assembly 10 includes a tab 11, and the electrode terminal 23 is electrically connected to the tab 11. The lead-out through hole 40 is provided at the electrode terminal 23, and the sensor 31 is provided at a side of the electrode terminal 23 facing the electrode assembly 10.

[0232] The electrode terminal 23 may be mounted on the end cap 22 or on the housing 21. For example, the electrode terminal 23 is mounted on the end cap 22.

[0233] The lead-out through hole 40 is provided on the electrode terminal 23 , so that the space utilization rate of the battery cell 6 can be improved.

[0234] The electrode terminal 23 has a higher strength than the housing 21 and the end cover 22. The lead-out through hole 40 is provided on the electrode terminal 23, so as to improve the stability of the detection component 30.

[0235] In some embodiments, the connector 32 may be bonded to the electrode terminal 23 or may be integrally formed with the electrode terminal 23 by hot melt.

[0236] In some embodiments, the battery cell 6 further includes a transition component 60 for connecting the tab 11 and the electrode terminal 23. The transition component 60 includes a terminal connection portion 611 that abuts against the surface of the electrode terminal 23 facing the electrode assembly 10, and the terminal connection portion 611 is provided with a second avoidance hole 612 opposite to the lead-out through hole 40. The sensor 31 is located on the side of the terminal connection portion 611 away from the electrode terminal 23, and the connector 32 extends into the lead-out through hole 40 via the second avoidance hole 612.

[0237] In the axial direction Y of the lead-out through hole 40 , the second avoidance hole 612 and the lead-out through hole 40 at least partially overlap.

[0238] By providing the second avoidance hole 612 , the risk of the adapter component 60 interfering with the connector 32 is reduced, so that the connector 32 can smoothly extend into the lead-out through hole 40 .

[0239] In some embodiments, the terminal connection portion 611 is spaced apart from the sensor 31 .

[0240] Setting the sensor 31 apart from the terminal connection portion 611 can provide space for the sensor 31 to move, thereby reducing the force at the connection between the sensor 31 and the connector 32 when the battery cell 6 vibrates, reducing the risk of connection failure between the sensor 31 and the connector 32, and improving the safety of the battery cell 6.

[0241] In some embodiments, the connector 32 does not protrude from the surface of the electrode terminal 23 facing away from the electrode assembly 10 .

[0242] The surface of the electrode terminal 23 facing away from the electrode assembly 10 usually needs to be connected to the busbar component. The embodiment of the present application can reduce the risk of interference between the connector 32 and the busbar component.

[0243] In some embodiments, the adapter component 60 includes an adapter body 62 and an adapter protrusion 61, wherein the adapter body 62 is connected to the electrode tab 11, and the adapter protrusion 61 protrudes from the surface of the adapter body 62 facing the electrode terminal 23. The adapter component 60 forms an adapter recess 63 at a position corresponding to the adapter protrusion 61, and the bottom wall of the adapter recess 63 forms a terminal connection portion 611. The sensor 31 is accommodated in the adapter recess 63.

[0244] The sensor 31 is arranged in the transfer recess 63 to improve the space utilization. The transfer recess 63 can limit the sensor 31 with its side wall to reduce the vibration amplitude of the sensor 31 when the battery cell 6 vibrates.

[0245] In some embodiments, the terminal connection portion 611 is welded to the electrode terminal 23. By providing the transition recess 63, the thickness of the terminal connection portion 611 can be reduced, thereby reducing the difficulty of welding the terminal connection portion 611 to the electrode terminal 23.

[0246] According to some embodiments of the present application, the present application also provides a battery, comprising a plurality of battery cells according to any one of the above embodiments.

[0247] According to some embodiments of the present application, the present application further provides an electric device, comprising a battery cell of any of the above embodiments, the battery cell is used to provide electric energy for the electric device. The electric device can be any of the above equipment or systems using the battery cell.

[0248] Reference Figures 3 to 5 According to the battery cell 6 of the embodiment of the present application, a square battery cell 6 is provided, which includes a shell 20, an electrode assembly 10 and a detection component 30. The shell 20 includes a shell 21 and an end cover 22, the shell 21 has an opening, and the end cover 22 is used to cover the opening. The shell 21 and the end cover 22 enclose a receiving cavity 20a. The electrode assembly 10 is received in the receiving cavity 20a. The end cover 22 is provided with a first through hole 221 communicating with the receiving cavity 20a.

[0249] The detection component 30 includes a sensor 31, a connecting member 32 and a fixing member 33. The connecting member 32 includes an optical fiber, and the connecting member 32 is connected to the sensor 31 and forms an optical fiber sensor 31 with the sensor 31.

[0250] The surface of the fixing member 33 facing the end cover 22 abuts against the end cover 22, and the fixing member 33 is welded to the end cover 22. The fixing member 33 is provided with a receiving recess 331 recessed from the surface of the fixing member 33 facing the end cover 22, and the receiving recess 331 is communicated with the first through hole 221. The bottom wall of the receiving recess 331 is provided with a second through hole 332. The sensor 31 is received in the receiving recess 331, and the connecting member 32 is connected to the fixing member 33 and passes through the second through hole 332.

[0251] The sensor 31 is used to detect the status information of the battery cell 6 and generate a signal, and the connector 32 is used to transmit the signal.

[0252] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0253] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein, but these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell, characterized in that: include: A housing having a receiving cavity, the housing comprising a shell and an end cover, the shell having an opening, and the end cover being used to cover the opening; An electrode assembly is accommodated in the accommodating cavity; as well as The detection component includes a sensor and a connector, wherein the sensor is connected to the end cover through the connector, and the sensor is used to detect the status information of the battery cell and generate a signal, and the connector is used to transmit the signal.

2. The battery cell according to claim 1, characterized in that: The state information of the battery cell includes at least one of an internal gas pressure of the battery cell, a temperature of the battery cell, an internal gas composition of the battery cell, and a deformation amount of the electrode assembly.

3. The battery cell according to claim 1, characterized in that: The connector includes an optical fiber.

4. The battery cell according to claim 1, characterized in that: The sensor includes at least one of a Bragg grating and a Fabry-Perot cavity.

5. The battery cell according to claim 1, characterized in that: The end cover is provided with a first through hole communicating with the accommodating cavity; The sensor is located on a side of the end cover facing away from the accommodating cavity, and the sensor is configured to detect status information of the battery cell through the first through hole.

6. The battery cell according to claim 5, characterized in that: In the axial direction of the first through hole, the sensor is opposite to the first through hole.

7. The battery cell according to claim 6, characterized in that: The sensor is connected to the end cover and covers the first through hole.

8. The battery cell according to claim 5, characterized in that: The detection component also includes a fixing member, and the connecting member is connected to the end cover through the fixing member.

9. The battery cell according to claim 8, characterized in that: The surface of the fixing member facing the end cover abuts against the end cover, and the fixing member is provided with a receiving recessed portion sunken from the surface of the fixing member facing the end cover, and the receiving recessed portion is communicated with the first through hole; The sensor is accommodated in the accommodating recess, and the connecting member is connected to the fixing member and passes through the fixing member.

10. The battery cell according to claim 9, characterized in that: A second through hole is formed on the bottom wall of the accommodating recess, and the connecting member passes through the fixing member via the second through hole.

11. The battery cell according to claim 10, characterized in that: The detection component further includes a sealing member, which connects a hole wall of the second through hole and the connecting member and seals the second through hole.

12. The battery cell according to claim 11, characterized in that: The sealing member is bonded to the hole wall of the second through hole and the connecting member.

13. The battery cell according to claim 9, characterized in that: The fixing member is welded to the end cover.

14. The battery cell according to claim 9, characterized in that: A positioning recess is provided on one side of the end cover away from the accommodating cavity, and the first through hole passes through the bottom wall of the positioning recess; At least a portion of the fixing member is accommodated in the positioning recess.

15. The battery cell according to claim 14, characterized in that: The fixing member includes a fixing body and a flange surrounding the outer side of the fixing body, the fixing body is provided with the accommodating recess, at least part of the flange is accommodated in the positioning recess, and the outer peripheral surface of the flange is connected to the side wall of the positioning recess.

16. The battery cell according to claim 15, characterized in that: The flange abuts against the bottom wall of the positioning recess.

17. The battery cell according to claim 9, characterized in that: The accommodating recess is step-shaped and includes a first section and a second section, wherein the second section is located on a side of the first section away from the first through hole; A cross section of the first section perpendicular to the axial direction of the first through hole is smaller than a cross section of the second section perpendicular to the axial direction of the first through hole; The sensor is housed in the second section.

18. The battery cell according to claim 9, characterized in that: The housing further comprises an electrode terminal disposed on the end cap, the electrode assembly comprises a tab, and the electrode terminal is electrically connected to the tab; In a direction perpendicular to the end cover, an end of the fixing member away from the end cover does not extend beyond the electrode terminal.

19. The battery cell according to claim 5, characterized in that: The battery cell is configured to be injected with an electrolyte through the first through hole.

20. The battery cell according to claim 1, characterized in that The end cover is provided with a lead-out through hole communicating with the accommodating cavity; The sensor is accommodated in the accommodating cavity, and at least a portion of the connecting member is accommodated in the lead-out through hole and connected to the end cover.

21. The battery cell according to claim 20, characterized in that: The detection component further includes a sealing member, which connects a hole wall of the lead-out through hole and the connecting member and seals the lead-out through hole.

22. The battery cell according to claim 20, characterized in that: An insulating layer is provided on a surface of the sensor facing the electrode assembly.

23. The battery cell according to claim 20, characterized in that: The sensor is located on a side of the end cover facing the electrode assembly and is spaced apart from the end cover.

24. The battery cell according to claim 23, characterized in that: The battery cell is configured to be injected with an electrolyte through the lead-out through-hole.

25. The battery cell according to claim 23, characterized in that: The battery cell further includes an insulating component disposed on a surface of the end cap facing the electrode assembly; The sensor is located on a side of the insulating component away from the end cover; the insulating component is provided with a first avoidance hole opposite to the lead-out through hole, and the connecting member extends into the lead-out through hole via the first avoidance hole.

26. The battery cell according to claim 25, characterized in that: The insulating component is spaced apart from the sensor.

27. The battery cell according to claim 23, characterized in that: A portion of the connecting member extends to the outside of the end cover through the lead-out through hole.

28. The battery cell according to claim 1, characterized in that: The battery cell is a cylindrical battery cell or a square battery cell.

29. A battery, characterized in that: The invention comprises a plurality of battery cells according to any one of claims 1 to 28.

30. An electrical device, characterized in that: The invention comprises a battery cell according to any one of claims 1 to 28, wherein the battery cell is used to provide electric energy.

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